Motor-controller.



G. R. HADLEY.

MOTOR CONTROLLER.

APPLICATION FILED JAN-25, 19l3.

1,144,431. Patented June 29, 1915;

. B v l l i l l l l WWW UNITED STATES PATENT" OFFICE.-

GUY R. RAD LEY, OF JVIILWAUKEE, WISCONSIN, ASSIGNOR TO THE CUTLER-HAMMER MFG. ('30., 0F ,MILWAUKEE, WISCONSIN, A' CORPORATION OF WISCONSIN.

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Specification of Letters Patent.

Patented June 29, 1915.-

i To all whom it may concern Be it known that I, GUY RIB- omer, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented new and useful Improvements in Motor-Controllers,

of which the following is a full, clear,.con.- cise, ,and exact-description, reference being had to the accompanying drawing, forming apart ofthis specification.

My invention relates to controllers for electric motors, andis particularly adapted to controllers for electric automobiles.

It has among "its objects to provide improved! means'for changing the field wind ings of the motors from series to parallel and vice versa.- 7

A further object is to provide a vehicle controller through which the. motor may be stopped by the emergency brake lever but which will positively preclude the motor from being restarted. by the emergency brake lever.

A further object is to rovide a vehicle controller which will ena le the motor to bestopped by either the emergency or service brakelevers and restarted by the service brake lever, but which will insure against restarting by the emergency brake lever.

My invention also has various other ob jects and advantages which .will hereinafter ap ear.

n order to clearly and fully disclose the nature and advantages of my invention I shall describe the controller diagrammatically illustrated'in the accompanying drawing, which embodies my invention 11 one form. It should, of course, be understood thatmy invention mlght be embodied in other forms than that selected for the purpose of illustration.

The controller illustrated in the accompanying drawing is of a type particularly suitable for electric automobiles and 'is shown as applied to one em loying a series motor which is supplied wit current from a single battery. The motor isillustrated as provided with an armature A and'two field ,coils' "F and F and as supplied with current from a battery B.

Briefly described, the controller comprises a number-of ma' netic switches controlled by a master switch ,a service brake lever SB, and an emergency brake lever EB in a manner heremafter set forth. The magnetic switches include a main line switch 10, a

starting resistance switch 11, a field control switch 12, an interlocking relay switch 13, and two throttling relay switchesll and 15 the former for the field switch .and the latter for the starting resistance switch. Relay switch 15 .may be omitted'if desired. The master iswitch M is schematically illustrated as of. the drum reverse type.. It is also illustrated as adapted-to control a re-- sistance R in series with the motor armasecond starting resistance R, in series with the motor. The master switch in its second position removesthe starting resistance R from circuit. The master switch in its third position energizes the resistance switch 11,

subject to the retardation by the throttling relay 15, to remove from circuit the resistance R. The master switch in its fourth position tends to deenergize the resistance switch 11 and energize the field switch 12 to connect the field windings in parallel subject to retardation by the throttling relay 14. The service brake lever operates a switch 16, which, when movedupon application of the brake first deenergizes the field switch or resistance switch, and then denergizes the main switch. Upon its return movement it first energizes the mainswitch and then energizes the resistance switch or field switch or both as will hereinafter appear. The interlocking relay switch 13 is also adapted to de'nergize the main switch 10 and thereby stop the motor. Further, the relay 13, when energized, is self-maintaininguntil the master switch is moved to off position. The function of this switch is to interlock the master switch and the emer gcncy brake switch. The emergency brake lever operates a switch 17 to energize the interlocking relay switch 13 when the emergency brake is applied. The emergency brake switch is therefore adapted to stop the -inotor but is ineffective to restart the motor. The transition of'the field windings from series to parallel is as follows. The step of starting resistance Rv is connected between the 'field windings, and, after removal from circuit by the switch 11, i's'reins'erted prior to operation ofthe field switch 12. To insure this reinsertion the switches 11 and '12 are preferably interlocked, as by means of the mechanical interlocking device 18, to

insure the opening of switch 11 prior'to' closure of the switch 12. Switch 12, by means of two poles, connects the two field windings and the resistance R in threecuit as the field windings are changed from series to parallel and vice versa. Its third function results from its connection in parallel with the field windings when connected in parallel. Due to this connection it further decreases the field strength of'the m0- tor and thereby causes an increased speed over that obtainable by mere parallel connection of the field windings. The utilization of a single resistance for these three functions is obviously very advantageous. The relay switch I l-also performs a plurality of functions- As above stated, it throt-- tles the field switch 12. It also performs another important function. As will be hereinaftermore fully set forth, it prevents a too quick reinsertion of the resistance R and a consequent delay in the'parallel connection of the field windings due to telegraphing of the relay and field switch should the master switch be moved quickly past the third position. It accomplishes this by establishing a circuit for the. switch 11 in shunt with the master switch and maintaining said circuit while abnormal conditions prevail in the motor circuit. This also is a very advantageous feature since electric vehicles are often operated by inexperienced and careless persons. v

More specifically set forth the operation of the controller is as follows. Let it be as sumed that the master switchis' moved for forward operation. Uponinitial movement in such-a direction the masterswitch-first establishes connections betweenits. contact fingers 20 and 22 and their respective segments 20 and 22. This establishes connections for the motor'which will cause it to operate in a forward direction when the main switch is closed. Upon continued movement of the master switch to its full first position, its fin- I gers 23 and 26 engage its segments 23" and 26respectively. This establishes a connection from the positive side of the battery by conductor 29 through finger 22 and segment 22 to segment 23% and finger 23 by conductor 30 through the operating winding of main switch 10, by conductor 31 through contact 16 of theservice brake switch. 16, by conductor 32 through the relay switch 13, which is normally in engagement with contact 13, and thence by conductorv 33 to the negative side of the battery The mam switch 10 thereupon closes, completing the motor circuit from segment 22 through the motor armature A to segment 21, thence to segment 20* and contact finger 20 through the resistance R by conductor 34 through,

main switch. 10 and through the operating winding of why 14, by conductor 35 throughthe field winding F, resistance R'.

winding of' relay 15 and field winding F, all in series. by conductor 36 to'the negative side of the battery. The motor is thus set in operation with two steps of starting resistance in series therewith and with its field windingsin series with one another. When the master switch 'is moved to its second position its finger 21 engages its segment 21, thereby sbo t-circuiting the startingresistance B. This constitutes the first step of ac celeration. The master switch when moved to its third position makes contact between its segment 24 and finger 24:. Thiscom pletes the circuit of the operating winding of the resistance switch 11. This circuit may be traced from the positive side of the battervto segment 22 thence .to segment 24 and-finger 24, by conductors 38 and 39 through the relav switch 15 by conductor 40 to the bperating winding of resistance switch 11, by conductors 41 and f2 through service brake switch 16 and its contact 16",.

by conductors 32' and 33 to the negative side .of the battery. The'switch 11 thereupon responds, subject to retardation by the relay switch 15 upon an excessive surge of ourrent-in the motor circuit and upon response short-circuits the resistance R. The short circuiting of the resistance R constitutes the second step of acceleration. The relay switch 15 may, as above set forth. be omitted if desired. The master switch upon movementto its fourth position first causes engagement of its finger 25 with segment 25 and then separation of its finger24 and segment 24. Senarationof finger 24 from segment 24* tends todeenergize the resistance switch'll, but, as just set forth, this operation do'es not occur until contact is made besults in completing the energizing circuit of the field switch 12. This circuit -may be traced from the positive side of the battery tion, by conductor 44 through theoperating winding offield switch 12, by conductor 42 tween finger 25 andsegment 25, which re- 1 parallel circuits including the two field coils and the resistance R and establishes these circuits'without interruption of the motor circuit. This is 'made possible by the use of the resistance R. The switch 12 is doua 'ble pole, being provided with two switch members 12 and 12". The member 12 completes a circuit'from the left hand termi- 11311 of the field winding F by conductors 45 and 46 to a point between the resistance R and the field windingsF', while the member 12, through conductor 47, connects a point a between the field winding F and resistance R to the negative side of the battery. Thus the threeparallel circuits may be traced as follows One circuit extends from conductor 35 through the field winding F and switch member 12 to the negative side of the battery. A second circuit extends from conductor 35 by conductor 45 through the switch member 12 by conductor 46 through the resistance R, by conductor 47 through the switch member 12 to the negative side of the battery. The third circuit may be traced from the conductor 35 to conductor 46 and thence through the field winding F by conductor 36-to the negative side of the battery. The

' tact.

connections of the fields in parallel, ofv

course, results in increasing the speed of the motor and the connection of the resistance in. parallel with the field windings augments the increase in speed. This constitutes the third ste of acceleration.

' The re ay switch 14 is. as above set forth,

.included in the energizing circuit of the field switch 12. The relay 14 has its operating winding in series with themotor and is adjusted to respond when the current conditions in the motor circuits are such as to render the parallel connection of the field windings undesirable. Accordingly should the relay 14 respond when the energizing circuit of the field switch is'closed by the master switch, said field switch will not respend until proper conditions are established in the motor circuit and the relay drops into engagement with its down con- This insures against the premature operation of the field switch. The relay switch 14 also performs another function. Upon-responding it engages an up contact connected to conductor 39, which, as before set forth, ,leads to the operating winding of switch 11. Thus when the relay switch 14 engages its up contact it connects theoperating winding of switch 11 to drum finger 25. Accordingly should relay 14 respond upon an attempt to energize the field switch, it would not only prevent the operation of the field switch but would maintain the resistance switch 11 energized and thereby maintain the resistance R short-circuited until time for the switch 12 to close. Otherwise in passing from position 3 to position 4 the resistance R might be reinserted in circuit a considerable length of time prior to operation of the field switch and thereby slow down the motor and accordingly delay acceleration thereof and undesirable -telegraphing of the relay switch 14 and field switch. Thus even though the master switch I is carelessly operated and moved too quickly past the third position the relay 14 will counteract the carelessness and cause the de sired operation of the controller.

The service brake switch 16, as above set forth, normally engages both of its contacts 16 and 16 Its contacts, however, are of diflerentsizes so that a partial movement will cause it to disengage contact 16, while a full movement will cause it to also disengage contact 16*. Bearing in mind that the contact 16 is in the circuit of the main line switch and the contact 16 in the circuits of. both the field switch and resistanceswitch, it will be seen that the service brake switch may be operated to either deenergize the resistance switch 11 or field switch 12 to slow down the motor or to deenergize the main switch 10 to stop themotor. It'will'restart the motor in any but the ofi position of the master controller. When operated to restart the motor it first engages contact 16 thereby energizing the mainswitch 10. Thereafter it engages its contact 16". This results in energizingresistance switch 11 or successively energizing resistance switch 11 l and field switch 12, or only energizingv field switch 12 according to the position of the master switch and the electrical conditions.

-When the master switch is in third position the service brake switch will obviously merely energize the resistance switch. 011- the other hand, if the master switch is in fourth position it may immediately energize the-field switchor it may first energize the resistance switch 11 and then the field switch according to the electrical conditions in the ,motor circuit and the action of the relay energize the same. In the latter event, or in brake switch, and when essential to the protection of the motor, tocause the magnetic switches to operate in the same sequence as when controlled by the master switch. On the 'other hand, the arrangement is such that a very rapid acceleration may be obtained through the medium. of the service'brake switch if not detrimental to the motor. The provision for this rapid acceleration is highly advantageous in the case of motor- ,vehicles which are often required to start very quickly to "avoid congestion of trafiic and to avoidcollisions.

Of course the resistance R is not utilized in restarting the motor by the service brake switch unless the master switch happens to be in its first position; this, however, is an advantage rather than a disadvantage. As

above set forth, rapid acceleration is often times highly desirable. The means controlled by the service brake switch affords full protection to the motor. Thus by omitting the resistance R step of acceleration from the service brake switch a more rapid acceleration is obtainable without endangering the motor. On the other hand, the

association of the resistance R with the master switch provides the operator with means for obtaining a more gradual acceleration'. if he desires to avail himself of the same, and this additional step of acceleration might be found very useful under some conditions. The emergency brake switch 17 i is also adapted-to stop the motor through the agency of the interlocking relay 13. This switch -is normally open and is adapted to be closed upon application of the emergency brake to complete the energizing circuit of the relay 13. This circuit may betraced from .the positive side .of the battery to finger 22, segment 22*, thence to segments 26 to finger 26 by conductor 50 through the operating winding of relay 13 and through contact, 13 of said relay by conductor 51 through the switch 17, by conductor 52 to the negative side of the battery. The interlocking relay thereupon responds, denergizing the main switch 10, and thereby disconnecting the motor from circuit. Also, upon responding the""relay switch 13 engages its contact'13 thereby establishing a self-maintaining circuit inparallel with the switch 17. The segment 26 of the master controller engages the finger 26 in all running positions of the master controller. It is therefore obvious that it is necessary to return the master switch to energizationj'bf the relay 13 is an essential prerequisite 'to the closure of the main line switch 10 and accordingly it is clearly impossible to restart the motor after the same has been stopped by the emergency brake switch witliput first returning the master switch to off position.

The reverse side of the master controller is provided with segments 21*, 23*, 24", and 26 which correspond to segments 21, 23, 24: and 26 and perform the same functions on reversal. In addition it is provided with segments 20 and 22 which perform the same functions as segments 20 and 22" except that they cause a reversal of the flow of current through. the motor armature and accordingly a reversal of the direction of operation of the motor. v a

What I claim as new and desire to secure byLetters Patent is:

1. A controller for an electric motor having alplurality of series field Windi gs comprising armature and fiGld'COHIIGCtIOHS for the motor, a single-throw switch for controlling said field connections to effect either series or parallel connection of the field windings and a resistance associated with said switch to maintain the continuity of field connections.

2'. A controller for an electric motor hav-" associated with said switch and said connections to maintain the continuity'of the motor circuit during said change in the field connections. 1

3.1 In a controller for motors having a plurality of series field windings, in combination, motor connections including varioff position to deenergizethe relay 13. De-

the motor circuit during-said change in said able connections for the motor field wind-,

ings, a resistance, and a single throw doublepole switch controlling said" variable field connections and said resistance to establish series connections for the field windings including said resistance or parallel connections for the field windings with a shunt therefor including said resistance; said switch efl'ecting said changes without interruption of the motor circuit.

4. In a controller for an electric motorhaving a plurality of series field windings, in combination, variable motor connections including, a series resistance and a single throw double-pole switch for varying said connections to establish parallel connection of the field windings with said re- I sistance in shunt therewith, said resistance maintaining the continuity of said motor connections during said change in the field connections. I

5. In a motor controller, in combination, two electro-responsive switches, one to be energized and deenergized prior to response of the other, and means automatically operating to retard the response of said latter switch and upon operation tending to prevent the deenergization of said former switch.

6. In a motor controller, in combination, two switches, one '-to be'energized and deenergized prior to response of the other, a common master switch therefor adapted when moved to a position to energize said latter switch to open the energizing circuit of the former switch, and means automatically operating to retard the responseof said second mentioned switch and to render said movement of said master switch ineffective to deenergize said first mentioned switch.

7 In combination, two electro-responsive accelerating switches one to be energized and denergized prior to response of the other, and a relay associated with said switches and automatically responsive under predetermined conditions to deenergize said latter switch and again energize said former switch.

8. In combination, two electro-responsive acceleration switches one to be energized and deenergized prior to-response of the other, a relay associated with said switches and automatically responsive under predetermined conditions to deenergize said latter switch and again energize said former switch, said relay upon returning to nor-' mal position successively deenergizing said former switch and energizing said latter switch. Y V

V -9. In acontroller for electric motors, in combination, two electro-responsive accelerating switches, and a relay responsive to the current conditions in the motor circuit, said relay upon responding preventing response of one of said switches and tending to maintain the other switch energized and upon returning to normal position deenergizing said latter switch and tending to energize said former switch.

10. In a motor controller, in combination, two electro-responsive switches, a controller therefor adapted when in one position to energize one of said switches-and movable to a'second position to energize the other switch and open the energizing circuit of lish an energizing circuit for said first a said first switch, and a relay adapted upon responding to interrupt the energlzmg c1rcuit ofsaid second switch and also estabswitch when said master controller is in second pos1t1on. i

11. In a motor controller, 1n combmation,

open the energizing circuit of said second switch andalso close an energizing circuit for said first switch when said master switch is in said second position.

12. In a controller for electric motors having a plurality of series field windings,

"in combination, a resistance to be included in the motor circuit, a switch for remov- 1ngsa1d' resistance to accelerate the motor, a

field switch for changing the connections of the motor field windings from series to parallel said latter switch being operable only after operation of said former switch to reinsert said resistance in circuit, and a relay switch operatively associated with both said resistance switch and said field switch.

13. In a controller for electric motors having aplurality of series field windings, in combination, a resistance to be included in the motor' circuit, a switch for removing said resistance to accelerate the motor a field switch for changing the connection of the motor field windings from series to parallel said latter switch being operable only after operation of said former switch to reinsert said resistance in circuit, and a 14. In a controllerfor electric motors having a plurality of series field windings, in combination, a resistance to be con-" nected between the motor field windings, an

electro-responsive switch for removing said L resistance from circuit to accelerate the moing said resistance to accomplish said change without interruption of the motor circuit,

means insuring the reinsertion of said resistance in circuit prior to operation of said second switch, and a relay responsive to the current conditions inthe motor circuit and adapted'lupon responding to interrupt the energizing circuit of said second switch and under predetermined conditions establish an energizing circuit for said first switch and to maintain said circuit until its return 0 normal position. v

15. n a controller for a motor having a plurality of series field windings, in combination, a resistance, and means for utilizing said resistance in series with the motor and in shunt with its field windings for separate steps of acceleration, said means including means for establishin either series or parallel connection of the eld windings and utilizing said resistance to maintain the a brake mechanism of the vehicle toenergize said relay to stop the motor.

17. In a controller for motor operated vehicles, in combination, electro-responsive starting and accelerating means, a master switch therefor, switches operatively con-- nected with the vehicle brake mechanisms for controlling said electro-responsive means to stop the motor, one of said latter switches being also adapted to restart the motor and means preventing restarting of the motor by the other of said switches.

18. In a controller for electric motor operated vehicles, in combination, a master switch for starting and stopping the driving motor, a service brake switch for stopping the motor and restarting the same when said master switch is in running position, an emergency brake switch for stopping the motor and an interlock between said switches necessitating restarting of the motor by said master switch after the motor has been stopped by said emergency brake.

switch.

19. In a controller for motor operated vehicles, in combination, manually controlled electro-responsive means for starting and accelerating the motor, a relay responsive to cause said means to stop the motor, and

a switch operated by a brake mechanism of the vehicle to energize said relay, said relay upon responding establishing a maintaining circuit for itself independent of said switch.

20. In a controller for electric motor operated vehicles, in combination, a switch operable at will for starting and stopping the driving motor, a switch operable by a brake mechanism ofthe vehicle to stop the motor and an interlock between said switches necessitating restarting of the mo-' tor by said first mentioned switch after the motor has been stopped by said second switch.

21. In a controller for electric motor operated vehicles, in combination, manually controlled electro-responsive means for starting and accelerating the motor, a brake operating member and means controlled by ond switch controlling said electro-responsive means and relay to start and stop the motor at will. 7

23. In a controller fora motor having a plurality of series field windings, the combination with a resistance normally connecting the field windings in series and limiting the starting current, of means for excluding said resistance and means for connecting the field windings in parallel, said means being interlocked to insure reinsertion of said resistance in circuit prior to establishment of parallel connections.

24. In-a controller for a motor having a plurality of series field windings, the combination with a resistance normally connectingthe field windings in series and limiting the starting current, ofelectroresponsive means for excluding said resistance from circuit andelectro-responsive means for connecting the field windings in parallel, said' means being interlocked to insure reinsertion of said resistance prior to establishment of said parallel connections.

25. In a controller for a motor'having a plurality of series .field windings, the combination with a resistance normally connecting the field windings in series and limiting the starting current, of means for excluding said resistance from circuit and means for connecting the field windings in parallel with one another and-said resistance,'said means being interlocked to insure reinsertion of said resistance in series with said field windings prior to establishment of said parallel connections. a In witness whereof, I have hereunto subscribed my name the presence of two witnesses. 4

. GUY R. R-ADLEY.

Witnesses:

F. H. HuimARn, S. A. WATSON. 

